I'll probably repost this in the forced induction section as well, but, I thought I would try some people over here as well..

I've got a Forged 355 with a Procharger D1 on it.. I keep spinning the Crank Hub right off the crank.. I keep breaking the woodruff keys.. This has happened about 6 times now.. I left the blower belt very loose this time (first few times, I saw over 15#'s of boost, now I was seeing roughly 10) .. Well, I spun the hub off again last night.. Broke the bolt that goes into the crank (a grade 8 bolt BTW) and now I have 1/2 a bolt in my crank.. The woodruff key looks like it melted to the crank or the hub (one of those from racenet..) melted and some of the metal is stuck to the crank..

I hear that a cog setup puts much less strain on the crank and therefor, probably won't pull the hub off.. I was thinking about getting an ATI SUperdamper and having the crank double keyed.. Any other ideas???

Not even sure if the crank is salvageable at this point.. GOtta take it over to the machine shop who built my engine and see what they say..

Thanks,

--Sean

 

This probably isnt the answer you want to here.....but you probably need to double key it. You could try a new keyed hub first...yours my be worn inside slightly.

 

On the high boost applications that I have seen, double keying was necessary. I did see two cases of the ATI Super Damper where the ATI billet hub cracked at the keyway. It is necessary to reinforce the outer diameter of the hub.

But your problem sounds more like there is too little interference in the fit of the hub to the crank. A "loose" hub would fatigue the bolt and the key.